import java.sql.Connection;

class Counter{
    public int count;

    synchronized public void increase()
    {
        count++;
    }

    public void increase2()
    {
        synchronized (this){
            count++;
        }
    }

    synchronized public static void increase3()
    {}

    public static void increase4(){
        synchronized (Counter.class){

        }
    }
}

//synchronized 使用方法
public class Demo14 {
    public static void main(String[] args) throws InterruptedException {
        Counter counter = new Counter();

        Thread t1 = new Thread(() -> {
            for(int i = 0; i < 50000; i++)
            {
                counter.increase();
            }
        });

        Thread t2 = new Thread(() -> {
            for(int i = 0; i < 50000; i++)
            {
                counter.increase();
            }
        });

        t1.start();
        t2.start();

        t1.join();
        t2.join();

        System.out.println(counter.count);
    }
}
